1. Field of the Invention
The present invention relates to a facsimile device equipped with a printed circuit board having major functions on an upper cover.
2. Related Background Art
A conventional facsimile device is constructed as shown in FIG. 1, as taught by U.S. Pat. No. 4,768,100.
A document sheet 102 mounted on a document sheet table 101 is fed from the right to the left in FIG. 1 by rollers 103, 104, 105 and 106 of the document sheet feeding means.
In the course of feed 107, the document sheet is illuminated by a light from a light source 108, and a reflected light is directed to mirrors 109 and 110, passes through a lens 111, is focused onto a photoelectric conversion element 112 such as a charge coupled device (CCD), and is converted to an electrical signal. Arranged above the document sheet feed means 103-106 is a printed circuit board which controls the function of operation (hereinafter referred to as OP CNT board), switching means is arranged thereon to permit external entry by an operator.
An upper half of the document sheet feed means 103-106 is accomodated in an operation panel unit which is operable around 114 in a direction of arrow A. Thus, when the document sheet jams, it can be readily removed by exposing the feed path.
A roll-shaped thermal record sheet 115 is located as shown at the center of the drawing, and printing is done thereon by cooperation of a thermal head 116 arranged below the document sheet table and a platen roller 117. The record sheet is fed out in a direction of arrow B.
Numeral 118 denotes a power supply, numeral 119 denotes a system control printed circuit board (SCNT board), and numeral 120 denotes a network control unit (NCU board) used for the connection with a telephone line. Power lines and signal lines (not shown) extend between the OP CNT board 113 and the SCNT board 119 and between the NCU board 120 and the SCNT board 119.
FIG. 2 shows another prior art facsimile device with a telephone set, which is disclosed in Japanese Patent Application Laid-Open No. 64-13356.
When a document sheet 131 is inserted to reach a feed roller 132, the feeding is started. An image is read by an image sensor 133 while the document sheet is pressed and fed in a direction of arrow C by a platen roller 134. An operation panel unit 135 is arranged above the document sheet feed means and an OP CNT board 136 is accomodated therein.
On the other hand, printing is made on a roll-shaped thermal record sheet 137 by cooperation of a thermal head 138 and a platen roller 139, and the record sheet is fed out of the device in a direction of arrow D. Numeral 140 denotes a power supply, numeral 141 denotes a board which includes a combination of the SCNT board 119 and the NCU board 120, and numeral 142 denotes a telephone circuit board which controls a speech network. Power lines and signal lines extend between the OP CNT board 136 and the SCNT board 119 and between the telephone circuit board and the SCNT board 119.
In the above-described prior art facsimile devices, the OP CNT 136 is located at the top due to necessity of operation, but other boards, SCNT 119, NCU 120 and the telephone circuit are distributedly arranged. Accordingly, harnessing is required to interconnect the boards.
The harnessing includes the following problems.
1 A space to arrange the harness is required.
2 Because the harnessing is done through clearances between mechanical units, a careful safety procedure is required to prevent touching a movable part of the mechanical units and a sharp edge. This lowers freedom of design of the mechanical units and imports various restrictions.
3 A connector to receive the harness is required on each of the boards. This is disadvantageous from a space-cost standpoint.
4 Where the OP CNT board 113 is mounted on the pivotable unit as shown in FIG. 1, the harness must pass through the center of pivot or some slack must be given to the harness. Further, a mechanism to prevent the harness from being bitten when the pivotable unit is opened and closed is required.
5 The more the number of harnesses in the device is and the longer the harness is, the more electromagnetic disturbances (EMI) occur. As a regulations on EMI are becoming more sever in these years, the countermeasurement therefor is difficult to attain and requires more cost.
6 The more the number of harnesses in the device is, the more trouble occurs with respect to productivity and quality. Accordingly, the reduction of harnesses is desirable.
The above problems relating to the harness may be solved if the respective boards are accomodated in one printed circuit board, but there are many restrictions which make it difficult to accomodate them in one board. Namely, the operation control function must be arranged at the top of the device because of its close relation with the operation panel, there is no sufficient space at the top of the device to accomodate one large printed circuit board, and a reader unit, a document sheet feed path, a record unit and a record sheet feed path are to be arranged to facilitate a process when the sheet jams.
Accordingly, in the prior art facsimile device, it is difficult to accommodate all boards in one printed circuit board, as a result, the problems relating to harnessing arise.